There's also the problem that outside offenses are just inside offenses with bonuses to outside shooting and penalties to inside shooting. The shot distribution is the same, and if you can't score inside you can't score.
This isn't strictly true, or at least, wasn't ~15 seasons ago when I looked at it. For example, in RnG, 47% of shots come from the guards, vs 36% in LI. On top of that, of those shots, in RnG, >40% of guard shots are from 3 vs only ~22% in LI.
You can certainly argue those splits should be bigger, but they definitely do exist.